By SAEED AHMED Several African-American leaders, including the Rev. Al Sharpton and Martin Luther King III, are expected to gather in Atlanta on Tuesday morning to announce a march on Washington, D.C., to demand that federal authorities intervene in the “huge outbreak” of hate crimes nationwide. The gathering will take place at 10 a.m. outside the Richard B. Russell building in downtown Atlanta.

Charles Steele, the president of the Southern Christian Leadership Conference, is scheduled to attend, as are representatives from the Nation of Islam and the National Association for the Advancement of Colored People. At the gathering, organizers will formally announce plans for the march on the nation’s capital that will take place Nov. 16. “In the history of the civil rights movements, we have often had to appeal to the federal government to intervene. That was certainly the case during my father’s era of leadership,” King said Monday night. “[The march next month] is an appeal to the federal government to do something about the crimes, such as the nooses that seem to be popping up all over the nation.”

Since a noose-hanging case on a high school campus in Jena, La., made headlines, there have been a number of other nooses found in incidents across the country: in a black Coast Guard cadet’s bag, on a Maryland college campus and, earlier this month, on the office door of a black professor at Columbia University in New York.

In Atlanta last week, a worker at a construction site for Atlanta’s Hartsfield-Jackson International Airport was fired for hanging a noose.

“Some people say it’s a prank or a joke. But there are some things you just don’t joke about,” King said.

Nooses are a symbol of the lynching violence of the segregation era. The Department of Justice already has created a task force to handle noose-hanging investigations. It investigated the Jena matter but decided not to prosecute because the federal government typically does not bring hate crimes charges against juveniles, the government said.

The march will also ask the federal government to intervene in other cases, such as the death of 14-year-old Martin Lee Anderson in Panama City, Fla. Last week, seven former boot camp guards and a nurse were acquitted of manslaughter in the death the boy who was hit and kicked by the drill instructors in a videotaped altercation. Anderson was black. The guards are white, black and Asian. The guards’ attorneys said Anderson’s death was unavoidable because he had undiagnosed sickle cell trait.